The present invention relates to a parasiticide for endoparasites, comprising, as the active ingredient, at least one natural or synthetic pyrethroid type compound, and to a method for exterminating endoparasites, which comprises orally or percutaneously administering said parasiticide.
In general, parasite diseases are caused when parasites, i.e. unicellular protozoans (Protozoa), multicellular Helminths, anthropods, etc. are parasitic on an animal host. It is reported that, in Japan, parasite diseases have decreased remarkably owing to the improvement in environmental hygiene and that the diseases are in wide spread worldwide, particularly in developing countries, giving considerable damage in these countries. However, in recent years, even in the developed countries, parasite diseases are beginning to increase owing to (1) the infection of long- or short-term travellers to developing countries, (2) the infection from imported foods or from the raw meat, raw fish and raw foods made available by the development of refrigeration and transportation techniques, and (3) the infection from pets.
Further, there is now a problem of opportunistic infection of parasites because non-pathogenic or low-pathogenic parasites come to aquire pathogenicity within a person who becomes immunodeficient owing to (1) the use of a large amount of drugs such as immunosuppressant and carcinostatic and (2) infective disease such as AIDS.
In addition, parasite diseases pose a general and serious economic problem in domestic animals such as pig, horse, cattle, sheep, goat, dog, cat, fowls.
The animals infected with parasite diseases incur anemia, malnutrition, asthenia, weight loss and serious damages of intestinal paries and other tissues and organs, which causes reduction in feed efficiency or productivity and invites a large economic loss. Thus, it is a long-standing important task to develop a novel parasiticidal or antiprotozoan agent.